# Finding Maximal Quasi-cliques Containing a Target Vertex in a Graph

### Yuan Heng Chou, En Tzu Wang, Arbee L. P. Chen

#### Abstract

Many real-world phenomena such as social networks and biological networks can be modeled as graphs. Discovering dense sub-graphs from these graphs may be able to find interesting facts about the phenomena. Quasi-cliques are a type of dense graphs, which is close to the complete graphs. In this paper, we want to find all maximal quasi-cliques containing a target vertex in the graph for some applications. A quasi-clique is defined as a maximal quasi-clique if it is not contained by any other quasi-cliques. We propose an algorithm to solve this problem and use several pruning techniques to improve the performance. Moreover, we propose another algorithm to solve a special case of this problem, i.e. finding the maximal cliques. The experiment results reveal that our method outperforms the previous work both in real and synthetic datasets in most cases.

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#### Paper Citation

#### in Harvard Style

Chou Y., Wang E. and Chen A. (2015). **Finding Maximal Quasi-cliques Containing a Target Vertex in a Graph** . In *Proceedings of 4th International Conference on Data Management Technologies and Applications - Volume 1: DATA,* ISBN 978-989-758-103-8, pages 5-15. DOI: 10.5220/0005498400050015

#### in Bibtex Style

@conference{data15,

author={Yuan Heng Chou and En Tzu Wang and Arbee L. P. Chen},

title={Finding Maximal Quasi-cliques Containing a Target Vertex in a Graph},

booktitle={Proceedings of 4th International Conference on Data Management Technologies and Applications - Volume 1: DATA,},

year={2015},

pages={5-15},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0005498400050015},

isbn={978-989-758-103-8},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of 4th International Conference on Data Management Technologies and Applications - Volume 1: DATA,

TI - Finding Maximal Quasi-cliques Containing a Target Vertex in a Graph

SN - 978-989-758-103-8

AU - Chou Y.

AU - Wang E.

AU - Chen A.

PY - 2015

SP - 5

EP - 15

DO - 10.5220/0005498400050015